1 Study the modal forms in blue in
sentences 1-4. Then answer questions a
and b.
1 She must have had a healthy lifestyle. She lived
until she was a hundred.
2 He can't have done a lot of exercise. He isn't very
fit.
3 She could have given up eating so much junk
food. She's lost a lot of weight.
4 My grandad might have smoked when he was
young. More people smoked in those days.
a Which of the past modal verbs
• expresses a strong probability that something
is true?
• expresses a strong probability that something
is not true?
• expresses a possibility that something
is true?
b When we speculate about the past, we make
sentences with a modal verb + + past
participle of the main verb.